3,047 research outputs found
Reply to ``Comment on `Test of constancy of speed of light with rotating cryogenic optical resonators' ''
An improved analysis of the Michelson-Morley-type experiment by P. Antonini
et al. (Phys. Rev. A. 71, 050101 (2005)) yields the Robertson-Mansouri-Sexl
theory parameter combination and the Standard Model Extension theory parameter
.Comment: 2 page
An experimental apparatus for measuring the Casimir effect at large distances
An experimental set-up for the measurement of the Casimir effect at
separations larger than a few microns is presented. The apparatus is based on a
mechanical resonator and uses a homodyne detection technique to sense the
Casimir force in the plane-parallel configuration. First measurements in the
3-10 micrometer range show an unexpected large force probably due to patch
effects.Comment: Proceedings of the workshop On the 60 Years on Casimir Effec
Test of constancy of speed of light with rotating cryogenic optical resonators
A test of Lorentz invariance for electromagnetic waves was performed by
comparing the resonance frequencies of two optical resonators as a function of
orientation in space. In terms of the Robertson-Mansouri-Sexl theory, we obtain
, a ten-fold improvement compared to
the previous best results. We also set a first upper limit for a so far unknown
parameter of the Standard Model Extension test theory,
.Comment: 4 pages, 2 figures, accepted for publication Phys. Rev. A (2005
A proposal for a comprehensive grading of Parkinson's disease severity combining motor and non-motor assessments: meeting an unmet need.
Non-motor symptoms are present in Parkinson's disease (PD) and a key determinant of quality of life. The Non-motor Symptoms Scale (NMSS) is a validated scale that allows quantifying frequency and severity (burden) of NMS. We report a proposal for using NMSS scores to determine levels of NMS burden (NMSB) and to complete PD patient classification
A rare cause of dysphagia due to retropharyngeal foregut duplication cyst: case report and review of the literature
Background: The retropharyngeal space is a deep compartment of the head and neck region which extends from the base of the skull to the mediastinum, between the posterior pharyngeal wall and vertebral muscles, delimited laterally by carotid sheaths. Pathological processes of the retropharyngeal space are rarely encountered, generally are isolated and painless masses often cystic, and they usually originate from branchial arch anomalies, but only in rare cases, they turn out to be foregut duplication cysts. Foregut duplication cyst is rare congenital malformations arising along primitively derived alimentary tract during the first trimester in the developing embryo, mostly seen in the thorax and abdomen, with just few cases reported in the head and neck region. We report an extremely rare case of a foregut duplication cyst lined with respiratory epithelium located in the retropharyngeal space, at the level of the oropharynx, of an adult patient with dysphagia surgically treated, and we also made an analysis of the published literature about this very uncommon condition. Case presentation: A 63-year-old male patient with chronic dysphagia was diagnosed with a retropharyngeal cystic lesion, which was surgically treated. Final pathologic evaluation confirmed the diagnosis of a rare foregut duplication cyst lined with respiratory epithelium. A review of the pertaining published literature about the head and neck foregut duplication cysts was made, with a particular emphasis on retropharyngeal ones. Conclusions: Retropharyngeal foregut duplication cysts are a very rare congenital cyst of the head and neck. Clinical symptoms such as dysphagia and dyspnea should be evaluated with fibrolaryngoscopy, and CT and MRI scans are of great significance for definitive diagnosis, which should include the possibility of a foregut duplication cyst in the differential diagnosis. Surgical excision is the elective treatment for this lesion, in order to prevent complications including infection and compression symptoms or eventually malignant transformation
Dominant BIN1-related centronuclear myopathy (CNM) revealed by lower limb myalgia and moderate CK elevation
We report a BIN1-related CNM family with unusual clinical phenotype. The proband, a 56-year-old man suffered of lower limbs myalgia since the age of 52. Clinical examination showed short stature, mild symmetric eyelid ptosis without ophthalmoplegia, scapular winging and Achilles tendon retraction. A muscle weakness was not noted. CK levels were up to 350 UI/L. Deltoid muscle biopsy showed nuclear centralization and clustering, deep sarcolemmal invaginations and type 1 fiber hypotrophy. Whole body MRI revealed fatty infiltration of posterior legs compartments, lumbar paraspinal and serratus muscles. Myotonic dystrophy type1 and 2, Pompe disease and MTM1 and DNM2-related CNM were ruled out. By sequencing BIN1, we identified a heterozygous pathogenic mutation [c.107C > A (p.A36E)], and we demonstrate that the mutation strongly impairs the membrane tubulation property of the protein. One affected sister carried the same mutation. Her clinical examination and muscle MRI revealed a similar phenotype. Our findings expand the clinical and genetic spectrum of the autosomal dominant CNM associated with BIN1 mutations
The Neural Correlates of Spatial and Object Working Memory in Elderly and Parkinson’s Disease Subjects
This fMRI study deals with the neural correlates of spatial and objects working memory (SWM and OWM) in elderly subjects (ESs) and idiopathic Parkinson’s disease (IPD). Normal aging and IPD can be associated with a WM decline. In IPD population, some studies reported similar SWM and OWM deficits; others reported a greater SWM than OWM impairment. In the present fMRI research, we investigated whether compensated IPD patients and elderly subjects with comparable performance during the execution of SWM and OWM tasks would present differences in WM-related brain activations. We found that the two groups recruited a prevalent left frontoparietal network when performing the SWM task and a bilateral network during OWM task execution. More specifically, the ESs showed bilateral frontal and subcortical activations in SWM, at difference with the IPD patients who showed a strict left lateralized network, consistent with frontostriatal degeneration in IPD. The overall brain activation in the IPD group was more extended as number of voxels with respect to ESs, suggesting underlying compensatory mechanisms. In conclusion, notwithstanding comparable WM performance, the two groups showed consistencies and differences in the WM activated networks. The latter underline the compensatory processes of normal typical and pathological aging
NGC 1300 Dynamics: II. The response models
We study the stellar response in a spectrum of potentials describing the
barred spiral galaxy NGC 1300. These potentials have been presented in a
previous paper and correspond to three different assumptions as regards the
geometry of the galaxy. For each potential we consider a wide range of
pattern speed values. Our goal is to discover the geometries and the
supporting specific morphological features of NGC 1300. For this
purpose we use the method of response models. In order to compare the images of
NGC 1300 with the density maps of our models, we define a new index which is a
generalization of the Hausdorff distance. This index helps us to find out
quantitatively which cases reproduce specific features of NGC 1300 in an
objective way. Furthermore, we construct alternative models following a
Schwarzschild type technique. By this method we vary the weights of the various
energy levels, and thus the orbital contribution of each energy, in order to
minimize the differences between the response density and that deduced from the
surface density of the galaxy, under certain assumptions. We find that the
models corresponding to \ksk and \ksk are
able to reproduce efficiently certain morphological features of NGC 1300, with
each one having its advantages and drawbacks.Comment: 13 pages, 10 figures, accepted for publication in MNRA
Evaluation of cefepime kinetic variables and milk production volume in goats
The objective of the present work was to investigate the correlation between the kinetic variables, and the volume of milk production, with and without a local inflammatory reaction induced by subcutaneous implants of a device for collecting tissue fluid.\n\n(Párrafo extraÃdo del texto a modo de resumen)</i
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